Look for horses, not zebra's. Although, Occam's razor has its limitations, it's often a good paradigm for medicine. Anorexia is much more common than Pick's Disease. You must read The Golden Cage by Hilde Bruch, MD.
This book is one of the best around for eating disorders. What it helps you realize is that the 1st step in anorexia is getting the patient back to a normal weight. Starvation affects cognition in a very significant way and can often lead to symptoms which seem like delusions or other schizophrenia symptoms.
It doesn't hurt to refer to a neurologist to officially rule out Pick's disease, but I'm not hearing you mention any of the typical frontal lobe symptoms seen with such (impulsive, and almost manic-like behaviors). Review these links:
I hope this helps. Let me know if you need more feedback. Good luck.
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